Also known as Larvikite, beautiful natural blue labradorite with grey/black background and chatoyant grey-blue flash. A type of feldspar with Mohs hardness of 6 to 6-1/2, this striking gemstone is named for the Larvik Fjords in Norway where it was first discovered in the 1880s, and where major deposits are still found. Machine-cut and drilled for consistent size, shape and drilling.